You need to get it plugged in to a proper diagnostics computer.
It often is the powersounder battery failing which causes this, but the alarm should shut up when you turn the ignition on.
Many independent garages, mobile technicians and auto-electricians have this equipment, and are usually much cheaper than the Vauxhall dealerships.
If you do get it plugged in make sure you tell them you have had fuses unplugged, as this will have logged in the cars memory as faults.
If you decide to just replace the powersounder there is a good "how-to" here (copy and paste link)-
http://www.vauxhallownersnetwork.co.uk/showthread.php?211454-How-2-Replace-Zafira-A-Power-Sounder
This is for Zafira "A".
Replacement unit available here, or search vauxhall power sounder -
http://cgi.ebay.co.uk/vauxhall-alarm-siren-power-sounder-part-no-9194454-/190456507146?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item2c5817ab0a
vaux
October 2010
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